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A novel laminated Al 2 O 3 /TiC/CaF 2-Al 2 O 3 /TiC sandwich ceramic composite was fabricated through cold pressing and sintering to achieve better anti-wear performance, such as low friction coefficient and low wear rate. Al 2 O 3 /TiC/CaF 2 and Al 2 O 3 /TiC composites were alternatively built layer-by-layer to obtain a sandwich structure. Solid lubricant CaF 2 was added evenly into the Al 2 O 3 /TiC/CaF 2 layer to reduce the friction and wear. Al 2 O 3 /TiC ceramic was also cold pressed and sintered for comparison. Friction analysis of the two ceramics was then conducted via a wear-and-tear machine. Worn surface and surface compositions were examined by scanning electron microscopy and energy dispersion spectrum, respectively. Results showed that the laminated Al 2 O 3 /TiC/CaF 2-Al 2 O 3 /TiC sandwich ceramic composite has lower friction coefficient and lower wear rate than those of Al 2 O 3 /TiC ceramic alone because of the addition of CaF 2 into the laminated Al 2 O 3 /TiC/CaF 2-Al 2 O 3 /TiC sandwich ceramic composite. Under the friction load, the tiny CaF 2 particles were scraped from the Al 2 O 3 /TiC/CaF 2 layer and spread on friction pairs before falling off into micropits. This process formed a smooth, self-lubricating film, which led to better anti-wear properties. Adhesive wear is the main wear mechanism of Al 2 O 3 /TiC/CaF 2 layer and abrasive wear is the main wear mechanism of Al 2 O 3 /TiC layer.

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Purpose This paper aims to thrash out friction and wear properties of automobile brake lining reinforced by lignin fiber and glass fiber in braking process. Design/methodology/approach ABAQUS finite element software was used to analyze thermo-mechanical coupled field of friction materials. XD-MSM constant speed friction testing machine was used to test friction and wear properties of friction material. Worn surface morphology and mechanism of friction materials were observed by using scanning electron microscope. Findings The results show that when the temperature was below 350°C, worn mechanism of MFBL was mainly fatigue wear and abrasive wear, and worn mechanism of GFBL was mainly fatigue wear because MFBL contained lignin fiber. Therefore, it exhibits better mechanical properties and friction and wear properties than those of GFBL. Originality/value Lignin fiber can improve mechanical properties and friction and wear properties of the automobile brake lining.